Answer:
b. closed circles on 1 and 4 with arrows pointing outward
Step-by-step explanation:
Which of the following describes the graph of {x | x < = 1} u {x | x > = 4},
We have been given the following set;
x < = 1
This set comprises of real numbers that are less than or equal to 1;
(1, 0, -1, -2, -3, -4, .......... -∞)
On the other hand, the set x > = 4 comprises of real numbers that are greater than or equal to 4;
(4, 5, 6, 7, 8, 9, ........∞)
The symbol ∪ means a union of sets. That is the set of numbers that belong in either or both sets;
{x | x < = 1} u {x | x > = 4} is same as writing;
(1, 0, -1, -2, -3, -4, .......... -∞) ∪ (4, 5, 6, 7, 8, 9, ........∞)
Therefore, the solution set will be closed circles on 1 and 4 with arrows pointing outward
Answer:
Closed circles on 1 and 4 with arrows pointing outward ⇒ answer b
Step-by-step explanation:
* Lets study the meaning of the inequality
- If a < x < b, that means the value of x is between a and b
- If a ≤ x ≤ b, that means the value of x is from a to b
- If x < a and x > b, that means the value of x is smaller than a and
grater than b
- If x ≤ a and x ≥ b, that means the value of x is smaller than or equal a and
grater than or equal b
* Now lets solve the problem
∵ {x I x ≤ 1}
∴ x is smaller than or equal 1
∵ {x I x ≥ 4}
∴ x is greater than or equal 4
∵ {x I x ≤1} ∪ {x I x ≥ 4}
- The meaning of ∪ is all numbers smaller than or equal 1 and all
the numbers greater than or equal 4
∴ {x I x ≤ 1} ∪ {x I x ≥ 4} = (-∞ , 1] ∪ [4 , ∞)
- This solution represented graphically by closed circles on 1 and
4 with arrows pointing outward
